Background
The shift register circuit consists of 3 SN74HC595 8-bit shift registers wired together to act as a 24 bit shift register. The circuit receives input from the HCS12. Shift registers consist of several flip flops that are tied together and pass information from the first flip flop to the next when a new input is received.
The shift register circuit consists of 3 SN74HC595 8-bit shift registers wired together to act as a 24 bit shift register. The circuit receives input from the HCS12. Shift registers consist of several flip flops that are tied together and pass information from the first flip flop to the next when a new input is received.
Implementation
The shift registers are connected together with all 3 inputs coming from the HCS12 into the first shift register and the inputted pattern is shifted 24 times until it has passed through each output once. Each time the pattern is shifted one bit an enable pulse is sent to the registers and the bit is displayed on the Matrix.
The shift registers are connected together with all 3 inputs coming from the HCS12 into the first shift register and the inputted pattern is shifted 24 times until it has passed through each output once. Each time the pattern is shifted one bit an enable pulse is sent to the registers and the bit is displayed on the Matrix.
Test Procedure
To test the shift registers we inputted a single bit into the first register and shifted it across the entire row.
Test Results
Our first test of the shift registers did not produce the expected results. The bit shifted properly for the first 8 columns but did not proceed any further. We checked our wiring and found we had wired the input for the second shift register wrong.
After fixing the input for the second shift register the bit shifted properly across the entire row. We verified the entire board was working by shifting the bit across all 6 rows.
To test the shift registers we inputted a single bit into the first register and shifted it across the entire row.
Test Results
Our first test of the shift registers did not produce the expected results. The bit shifted properly for the first 8 columns but did not proceed any further. We checked our wiring and found we had wired the input for the second shift register wrong.
After fixing the input for the second shift register the bit shifted properly across the entire row. We verified the entire board was working by shifting the bit across all 6 rows.